A systems perspective is offered of cooperation among various agencies providing educational and related services to severely emotionally disturbed children. The systems view is described in terms of interfaces of four subsystems which exist in each agency--structural, technological, human, and communication. The structural interface involves funding arrangements and written agreements. The specialized expertise of educational and mental health professionals are considered as the technology interface. The human interface includes exchanges between people in agencies; while the communication interface deals with the exchange of information between agencies. The Assessement Survey of Interagency Relations is offered to identify the factors which are seen as helping or hindering cooperation between the educational and mental agencies. (SW)